NEW YORK (Reuters Health) - The risk of serious infections
increases in the early months of anti-TNF treatment for
inflammatory bowel disease, researchers from Denmark report.

"The pro-inflammatory cytokine TNF-alpha plays an important
role in the immune system and therefore it is biologically
plausible that TNF-alpha inhibitors may increase the risk of
infections," said Dr. Nynne Nyboe Andersen from Statens Serum
Institute in Copenhagen.

"Our findings of an increased risk of infections in the
early phase after treatment initiation and a subsequent decline
in risk are in accordance with other studies based on people
with rheumatoid arthritis," she told Reuters Health by email.

For their study, online June 5 in BMJ, Dr. Andersen's team
used data from linked Danish registries on nearly 52,400 people
with inflammatory bowel disease, among whom 4,300 were treated
with TNF-alpha inhibitors.

The risk of serious infections in the first 90 days of
treatment increased by 63%, from an incidence of 9 per 100
person-years among nonusers to an incidence of 14 per 100
person-years among anti-TNF-alpha users, the researchers found.

The risk of serious infection over the first 365 days,
however, was not significantly different between TNF-alpha
inhibitor users and nonusers.

In matched analyses, the use of TNF-alpha inhibitors was
associated with an 81% higher risk of serious infections in the
first 90 days of treatment and a 52% increased risk of serious
infections in the first 365 days of treatment.

"It is important to stress that the benefit of TNF-alpha
inhibitor treatment in people with inflammatory bowel disease is
unquestionable," Dr. Andersen concluded. "However, our findings
call for a clinical awareness of potential infectious
complications among people using these drugs, particularly early
in the course of treatment."

Dr. Andersen added, "We would like to point out that the
study's ability to conclude on specific infections and on
different TNF-alpha inhibitors separately was limited because of
power issues and should be assessed in future even larger-scale
population-based studies."

Dr. Julio Maria Fonseca Chebli from Inflammatory Bowel
Disease Center, Federal University of Juiz de Fora in Brazil,
said, "All physicians who use TNF-alpha inhibitors must have in
their mind that a strict evaluation must be done about patient's
immunity in reference to those infections that are more frequent
in such circumstances, including tuberculosis, influenza,
hepatitis B and C, pneumonia, and others, if appropriate
vaccines are not employed before beginning treatment."

"All doctors who deal with IBD therapy with TNF-alpha
inhibitors will reinforce their attention in the first ninety
days, especially to skin and soft tissue infections," Dr.
Chebli, who was not involved in the study, told Reuters Health
by email. "Other studies need to be done to conclude if this
reduction after ninety days is maintained."